Needle-bar mechanism for sewing-machines.



PATEN' I'BD SEPT. 15, 1903. E. B. ALLEN. NEEDLE BAR MECHANISM FOR SEWING MACHINES.

APPLICATION FILED JUNE 13, 1902.

2 SHEETB-SHEET 1.

I0 MODEL.

I PATBNTED SEPT. 15, 1903. E E. ALLEN. NEEDLE BAR MECHANISM FOR SEWING MACHINES.

APPLICATION FILED JUNE 13. 1902.

2 SHEETS-SHEET 2.

H0 MODEL.

Invenior;

n'uo, WASHINGTON, n. c.

v UNITED V STATES Patented September 15, 1903.

PATENT OFFICE.

EDWARD B. ALLEN, OF ELIZABETH, NEW JERSEY, ASSIGNOR TO THE SINGER MANUFACTURING COMPANY, A CORPORATION OF NEW JERSEY.

NEEDLE-BAR MECHANISM FOR SEWING-'MACHINES.

SPECIFICATION forming part of Letters Patent No. 739,132, dated September 15, 1903. Application filed June 13, 1902. Serial No. 111,474. (No model.)

To aZZ nrhom it may concern! Be it known that L'EDWARD B. ALLEN, a citizen of the United States, residing at Elizabeth, in the county of Union and State of New Jersey, have invented certain new and useful Improvements in Needle-Bar Mechanisms for Sewing-Machines, ofwhich the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to that class of needle-bar-operating mechanisms by which differential or irregular movements are imparted to the needle-bars of sewing-machin es for the purpose of securing a proper or desired timparts when only one needle is employed or relative to the other parts and to each other Where a plurality of needles are to operate in one machine.

The invention is more particularly designed for use in driving two out-of-time needles 00- operating with a thread-carrying and a non thread-carrying looper, acting alternately for the production of overseaming or buttonholestitching, as fully shown and described in my application, Serial No. 2 1,679, filed July 17, 1900, and the two out-of-time needle-bars of the present I invention are preferably so mounted as to be adapted to be turned, as

for stitching around the eyes of buttonholes or for other work.

In the accompanying drawings, Figure 1 is a front view of the head of a sewing-machine embodying the invention, the face-plate being removed and parts being broken out. Fig. 2 is atop view of the same, partly in horizontal section. Fig. 3 is a detail View showing the crank-head and double crank.

'Fig. 4 is an elevation of a needle-bar guide in which two needle-bars adapted for rotary or turning movements are mounted in such sides of the cylindrical needle-bar l9. tween the lugs 22 on the longer needle-bar 20 a manner as to be capable of operative connection with a double crank. Fig. 5 is a Ver tical sectionof the structure shown by Fig. 4, and Fig. 6 is a top view of the same. Figs. 7 and 8 are detail cross-sections on lines 7 7 and 8 8, respectively, of Fig.4.

Referring to the drawings, 12 denotes the head or forward part of the bracket-arm of a sewing-machine, and 13 is a rotary needlebar-operating shaft to which is secured a crank-head 14, carrying a rigidly-fixed double crank comprising the crank-pins 15 and 16, connected by the bar or web 17, said parts 15, 16, and 17 being preferably an integral forging.

Mounted for horizontal rotation in suitable vertical bearings in the head 12 is a needle* bar guide 19, which is circular in cross-section, said needle-bar guide beingin the present instance provided with vertical grooves for the receptionzof two needle-bars 20 and '21, having close sliding fits intheir grooves.

Each needle-bar is provided near its upper end with lugs 22, projecting out beyondthe is fitted a collar 23, closely embracing the needle-bar guide 19 andprovided with a pin 24, connected by a link 25 with the outer end of a radius-bar 26, which is in turn connected between its ends with the inner crank-pin 15 by a link 27, said radius-bar 26 being pivoted at 28 to a lug 29 within the head 12. Fitting between the lugs 22 near the upper end of the shorter needle-bar 21 is a collar 30, encircling the needle-bar guide 19 and having apin 31, connected by a link 32 to the outer or free end of a radius-bar 33, pivoted at 34: to a lug 35 within the head 12 and connected between its ends by a link '36 with the outer crankpin 16.

The above-described construction enables the needle-bars to be reciprocated vertically in their slots or guideways in the needle-bar guide 19, the collars 23 and 30 reciprocating 9 the said needle-bars with their driving crankins.

p The needle-bars are preferably grooved on their inner faces, as shown, to lighten them, and the needle-bar guide 19 is preferably provided with vertical grooves 37, extending from top to bottom thereof and down through which the threads to the needles 38 may be led, said grooves 37 being preferably covered by small plates 39 to protect the threads from oil. Attached to the needle-bar guide 19, so as to turn therewith and with the needle-bars and needles, is a bracket 40, which pivotally supports the upper looper 41, cooperating with the needles in the formation of overseaming-stitches, as fully set forth in my said application Serial No. 24,679.

In the construction herein illustrated the cranks 15 and 16 are onehundred and eighty degrees apart, or approximatelyso, so that the out-of-time needles reciprocate alternately, one going down when the other is going up; but owing to the above-described connections of the needle-bar with their operating-cranks through the links and radius-bars and which radi us-bars are arranged to extend across the plane (transversely of the machine) in which the needle-bars and their operating rotating shaft are mounted the reciprocating movements of said needle-bars will be irregular or diiferential, the said movements of the said bars being comparatively slow during the upper portions of their strokes and very rapid during the lower portions of their strokes. From this operation it results that the needles enter the work quickly and are quickly withdrawn therefrom, and as they move so comparatively slow during the upper parts of their strokes they will both be above the work at the same time during a considerable part of the rotation of the driving-shaft 13, allowing proper time for the feed of thework While both of the out-of-time needles are out of the work and enabling the machine to be stopped at the completion of a stitching operation with both needles above the work or above a buttonhole-maehine work-clamp in which the work may be held.

The invention is not to be understood as being limited to the details of construction herein shown and described or to the particular arrangements of the parts herein shown, as by a reverse arrangement of the links and a radius-bar to an operating crankpin from that herein shown an irregular or differential movement may be imparted to a needle-bar in such a manner as to cause the said needle-bar to move comparatively slowly during the lower part of its stroke and more rapidly during the upper part of its stroke, as is desirable with some kinds of sewing-machines. Also the invention is not to be understood as being limited to two out-of-time needle-bars mounted for periodical rotation, or, in fact, to two needle-bars at all, as it may be utilized for operating a single needle-bar with a differential movement through a radius-bar extending across the head of the machine and connected between its ends to a rotating crank by a link and having its free end connected by a link to the needlebar to be operated.

I Having thus described my invention, I claim and desire to secure by Letters Patent 1. In a sewing-machine, the combination with a rotating crank within the head of the machine, of a needle-bar, a radius-bar pivoted at one end to a fixed part of and within the machine-head, a link jointed to said crank at one end, and also jointed to the said radius-bar, between the ends of the latter, at its other end, and a second link connecting the free end of said radius-bar with said needle-bar.

2. In a sewing-machine, the combination with a rotating crank within the head of the machine, of a needle-bar, a. radius-bar pivoted at one end to a fixed part and within the head ofthe machine at one side of the needle-bar and extending across the said head beyond or to the other side of the said needlebar, a link jointed to said crank at one end, and also jointed to said radius-bar, between the ends of the latter, at its other end, anda second link connecting the free end of said radius-bar with said needle-bar.

3. In a sewing-machine, the combination with a rotating double crank and two needlebars, of two radius-bars, two links each connected at one end to a different pin or part of the said double crank and each jointed at its other end to a radius-bar between the ends of the latter, and two other'links each of which connects one of said needle-bars with the free end of one of said radius-bars.

4. In a sewing-machine, the combination of a cylindrical needle-bar guide adapted to be turned and having two grooves, of two needlebars fitted to reciprocate in said grooves, two collars fitted to slide on said cylindrical needlebar guide and operatively connected with said needle-bars, and means for reciprocating said needle-bars in their rotative guide.

5. In a sewing-machine, the combination with a double crank, of a cylindrical needlebar guide adapted to rotate and having two grooves, two needle-bars fitted to reciprocate in said grooves, two collars fittted to slide on said needle-bar guide and operatively connected with said needle-bars, two radius-bars, two links each connected at one end to a pin or part of said'double crank and each jointed at its other end to a radius-bar between the ends of the latter, and two other links each of which connects one of said collars with the free end of one of said radius-bars.

6. In a sewing-machine, the combination with a double crank, of a cylindrical needlebar guide adapted to rotate and having two grooves, two needle-bars fitted to reciprocate in said grooves, two collars fitted to slide on said needle-bar guide and operatively connected with said needle-bars, two radius-bars,

two links eachconnected at one end to a pin so that the said needle-bar guide and needleor part of said double crank and each jointed bars may be turned in said .collars without at its other end to a radius-bar between the disturbing the said operative connection.

f ends of the latter, and two other links each In testimony whereof I affix my signature 5 of which connects one of said collars with the in. presence of two witnesses.

free end of one of said radius-bars, the operative connection of said needle-bars and col- EDWARD L lars comprising lugs on said needle-bars pro- W'itnesses: jectiug outside of said needle-bar guide and HENRY J. MILLER,

IO between which lugs said collars closely fit; HENRY A. KORNEMANN. 

